Adjustable drill guide



Feb. 6, 1951 A. FEUcHT 2,540,574

ADJUSTABLE DRILL GUIDE Fiied Jan. :5o. 194e ATTORNEYS Patented Feb. 6, 1951 ADJUSTABLE DRILL GUIDE Albert Feucht, Garfield Heights, Ohio, assignor, by mesne assignments, to Le Roi Company, Milwaukee, Wis., a corporation of Wisconsin Application January 30, 1946, Serial No. 644,385

(o1. rZ55-51) 1 Claim.

This invention relates to improvements in adjustable drill guides, and has to do more particularly with guides of the type known as centralizers for guiding the drill steel in a rock drilling machine.

A drill hole must be maintained straight, as otherwise the drill would bind against the sides of the hole, in hard rock especially. To prevent the drill from Wandering, particularly While the hole is being started, a rigidly supported drill guide is employed close to the surface oi the rock in which the'hole is to be drilled. When the hole has been drilled to a depth such that the walis thereof will function effectively for holding the drill in alignment the guide may be removed and the hole completed Without it.

One of the objects of the present invention is the provision of a guide of the character stated having means for adjustment to compensate for wear in the bushing surrounding the drill shaft, or for limited dilerences in diameter of the drill shafts used.

Another object is the provision of a drill guide or centralizer of rugged design that is of simple construction and is quick acting in operation.

Other objects and features of novelty will appear as I proceed with the description of that embodiment of the invention which, for the purposes of the present application I have illustrated in the accompanying drawing, in which Fig. l is a side elevational View of a rock drilling machine oi the wagon drill type embodying the invention.

Fig. 2 is a iragmental elevational view on a larger scale oi that portion of the machine in which the present invention is embodied.

Fig. 3 is an elevational view looking in the direction of the arrow in Fig. 2.

Figs. 4 and 5 are cross-sectional views taken substantially on the lines 1 -ii and 5-5 respectively of Fig. 2.

Fig. 6 is a fragmental sectional View similar to Fig. 4 but with the parts in a different position of adjustment. g

Fig. 7 is a vertical sectional view taken substantially on the line lof Fig. 4.

Fig. 8 is a similar View taken substantially on the line 8-3 of Fig. S, and

Fig. 9 is a cross-sectional view on a smaller scale, corresponding to the section line ll-Li of Fig. 2 but showing the free ends of the guide arms disconnected and swung away from the drill steel.

The invention is illustrated in Fig. l as applied to a wagon type drilling machine, although the mounting of the mechanism upon any suitable type of support is well within the scope of the invention. In the drawing there is shown a frame structure l5 carrying an adjustable brace made up of three elements l5, il and I8 forming the sides of a triangle. The element i3 is adjustable as to length. On the end oi element l1 there is fastened by a lockable pivot construction a conventional rock drill supporting and ieeding mechanism 2t carrying a drill motor 2i with a drill steel The construction described in the foregoing is conventional, and forms no part oi the present invention.

The assembly in which the present invention is embodied is located on the extreme end o1 the drill supporting and feeding mechanism 2t near the rock to be drilled, and is marked 23 in Fig. l. The supporting and feeding mechanism 2d embodies two angle irons 2d and 25, to each oi' which are secured upper and lower brackets 25 2l' that support pins or shafts 2t and 29. These shafts carry a pair of arms til and 3l that have elongated hinge portions 32 that extend above and below the arms proper and are bored to receive the shaft 22 or 2:?, as the case may be.

The arms 3i! and 3i are shaped to clear the angle irons 2li' and 25, passing around them and converging toward each other at their ree ends when the device is in operative position. Near their free ends these arms are provided with curved recesses to receive the two sections 33 and 34 of a split bushing that is designed to substantially surround and forni a rotary and slide bearing for the drill steel Z2. The two sections of the bushing are somewhat lessvthan half cylinders, and are secured within their sockets by means oi cap screws 35 and 3S or other suitable means.

The free extremity of arm 3l has an extension 3l with a face 38 that may be ush with the edge surfaces of bushing section 34. Arm 30 has an extension 39 with a serrated face 40 that is perpendicular to face 38 when the guide is in operative position. A block lil with serrations matching those of face 40 is adjustably mounted on the extension 39, preferably by means of a pair of bolts 42 which are set into round holes in the extension 39 and project through slots 43 in block 4l. By loosening the bolts 42 the block 4I may be moved toward or away from the face 38, two different positions being indicated in Figs. 4 and 6. When the bolts i2 are' tightened they, in combination with the matching serrations, accomplish a rigid mounting of the block on the extension 39.

Extension 3l is provided with a groove 44 of cylindrical contour in which are mounted Vtwo spaced steel cylinders or spacers 45 and 46. These cylinders are held in the groove 44 by suitable means, for example by cap screws 41 which project through holes in the extension 31 and are threaded into tapped holes in the cylinders. When the arms come together the spacers 45 and 46 fit into a groove 55 in block 4|. The grooves 44 and 55 are of less than semi-cylindrical shape, and hence the elements 31 and 4| are spaced apart as indicated in both of Figs. 4 and 6. Projections 55 and 51 on the hinge ends of arms 30 and 3| serve to engage angle irons 24 and 25 and thus constitute stops to prevent the swinging of the arms beyond the positions illustrated in Fig. 9.

The block 4| is bored throughout its length to receive a pivot pin 48 which is pressed or driven into the bore, and the block is further formed with a transverse slot 49 which intersects the bore for pin 48 and receives the eye portion of an eye bolt 50 that turns upon pin 48 and is adapted to swing through a slot 5| in extension 31 when the arms 39 and 3| are swung into operative relation. The arms may then be clamped together by means of a knurled nut 52 threaded onto the eye bolt 50.

Operation. With the guide arms 30 and 3| in the position of Fig. 9 the feed mechanism 20 and drill motor` 2| are operated to bring the drill bit end of the drill steel 22 into contact substantially with the surface of the rock to be drilled. The guide arms 30 and 3| are then swung from the position of Fig. 9 around to the position of Figs. 4 and 5, when the bushing sections 33 and 34 engage the drill shaft. The eye bolt is then swung around through the slot 5| and the nut 52 is tightened down to clamp the free ends of the arms together with the spacers 45 and 45 between them. The motor 2| is then turned on and the drill operated until the hole in the rock is well started, after which the clamp may be loosened and the arms 39 and 3| separated. The drilling operation is then resumed and continued until a hole of the desired depth has been formed.

When the bushing sections 33 and 34 have be- ,4,

come worn to such an extent that their guiding function is impaired, the block 4| may be adjusted outwardly, as indicated in Fig. 6, with the result.

a somewhat larger or smaller diameter than that for which the bushing sections are primarily intended, the adjustment of block 4| inwardly or outwardly upon the extension 39 will permit such use without a change in bushing sections. Obviously, however, further changes may be effected by substituting bushing sections of different thicknesses and contour.

In the foregoing description Ihave necessarily gone somewhat into detail in order to explain fully the particular embodiment of the invention herein illustrated, but I desire it to be understood that such detail disclosure is not to be construed as amounting to a-limitation, except as it may be included in the appended claim.

Having thus described my invention, I claim:

In a drill steel centralizer, a pair of arms each carrying one section of a split cylindrical bushing adapted to form a rotary and slide bearing for the drill steel, said arms having parallel edge sur faces, a pivot pin for each of said arms whose axis is parallel to the axis of said bearing, an extension on the extremity lof one of said arms having a face substantially parallel to a continuation of the edge surfaces of its split bushing, an extension on the extremity of the second arm having a surface substantially perpendicular to its edge surface when said arms are in operative position, a block releasably mounted on said perpendicular surface, said releasable connecting means between said block and said perpendicular surface consisting of matching serrated surfaces and locking means enabling adjustment of the block 'toward and away from the edge surface on said rst named arm, a cylindrical spacer xedly mounted on the extension of said rst named arm whose axis is in parallel with the axis of said bearing, a partly cylindrical groove on the adjacent end of said block adapted to iit over said spacer for spacing said arms apart, and a clamp for securing said arms together with said spacer therebetween.

ALBERT FEUCHT.

REFERENCES CITED The following references are of record in the le of this patenti UNITED STATES PATENTS Number Name Date 719,766 Downing Feb. 3, 1903 1,149,557 Derrick Aug. 10, 1915 1,433,623 Johnston Oct. 31, 1922 2,357,001 Hope Aug. 29, 1944 2,365,683 Curtis et al Dec. 26, 1944 

